P070 Effect of insulin resistance on treatment response in moderate-to-severe psoriasis: a retrospective study

Abstract Psoriasis is associated with metabolic syndrome and insulin resistance (IR). Recent studies have shown IR to be a predictor of response to various biologic treatments in patients with psoriasis (Huang D, Zhong X, Jiang Y et al. Insulin resistance impairs biologic agent response in moderate-to-severe plaque psoriasis: insights from a prospective cohort study in China. Br J Dermatol 2024; 191: 616–23). We hereby tried to analyse treatment response to the systemic nonbiologic modalities with respect to IR in patients with moderate-to-severe psoriasis. This single-centre retrospective study was carried out at a tertiary care institute. Data were retrieved and analysed for patients with moderate-to-severe psoriasis registered in the psoriasis clinic from January 2023 to June 2024 who received systemic nonbiologic treatment with a minimum follow-up of 12 weeks. Psoriasis severity was assessed using the Psoriasis Area and Severity Index (PASI). IR was calculated using triglyceride glucose–body mass index (TyG-BMI) and homeostasis model assessment of insulin resistance (HOMA-IR). Treatment response was assessed as ≥ 75% improvement in PASI (PASI 75) at 12 weeks. In total 34 patients with moderate-to-severe psoriasis were analysed. The mean (SD) age of the study population was 42.7 (13.6) years; 22 patients were male and 12 female ratio. Of the 34 patients, 11 had metabolic syndrome and five had psoriatic arthritis. The mean duration of the disease was 9.5 (SD 6.9) years. The mean (SD) baseline body surface area (BSA) and PASI were 19.1% (17.4) and 9.1 (5.7), respectively. Twenty-four patients received methotrexate and 10 patients received apremilast. The mean (SD) TyG-BMI index was 222 (33.4). Mean (SD) insulin and HOMA-IR were 13.5 mIU L−1 (8.8) and 3.2 (1.9), respectively. Among the patients with a high TyG-BMI index (i.e. above the median of 223), nine of 17 (53%) achieved PASI 75, while seven of 17 patients (41%) with a low TyG-BMI index achieved PASI 75 at week 12 (P = 0.73). However, among patients with high HOMA-IR (> 2.9), only 4 of 15 (27%) achieved PASI 75 at week 12, compared with 12 of 19 (63%) with low HOMA-IR (P = 0.04). Significant differences were observed in the decrease in BSA and PASI at week 12 between patients with high and low HOMA-IR (P = 0.02 and P = 0.03, respectively). In contrast, no such significance was observed with respect to TyG-BMI (P = 0.6 and P = 0.8, respectively). In conclusion, our study shows that a high HOMA-IR index, not a TyG-BMI index, impairs treatment response to systemic drugs in patients with moderate-to-severe psoriasis. However, our study has limitations such as the small sample size and retrospective design. Thus, prospective studies with larger patient populations are needed to evaluate the long-term impact of IR in psoriasis.